DE102020117913A1 - Process for manufacturing a pressurized gas tank for a motor vehicle - Google Patents

Abstract

The invention relates to a method for producing a compressed gas tank (1) for a motor vehicle, a housing (2) of the compressed gas tank (1) being provided which has an axially extending housing opening (4.1). In order to enable a compressed gas tank of a motor vehicle to be filled efficiently, the invention provides that a bundle (10) of heat-conducting elements (11) is inserted at least partially into the housing (2) through the housing opening (4.1) with a first end (10.1) first and thereafter at least one force is applied to a second end (10.2) of the bundle (10), whereby the bundle (10) expands radially within the housing (2).

Description

The invention relates to a method for producing a compressed gas tank for a motor vehicle.

Pressurized gas tanks or pressure vessels are used in the automotive sector, for example to hold natural gas, LPG or hydrogen for fuel cells. The pressurized gas tank usually has a cylindrical middle section, which is adjoined by curved or dome-like end sections. A compressed gas tank usually has an inner shell which is surrounded by an outer shell which consists of continuous fibers (rovings) wound in a polymer matrix. Fiber reinforcement is often essential for adequate compressive strength. There are known pressurized gas tanks that are made exclusively of metal, as well as those that are made of metal and fiber-reinforced exclusively in the cylindrical central section. Other compressed gas tanks have an inner shell made of metal and are fiber-reinforced both in the middle section and in the end sections, still others have an inner shell made of a polymer, which is fiber-reinforced in the middle section and in the end sections and the end metal end pieces for a valve or a closure. During refueling, the compressed gas tank heats up considerably, mainly due to the compression of the gas inside the tank (and possibly in a line leading to the tank). There may be a risk that a maximum tank temperature specified for safety reasons will be exceeded. In order to prevent this, either refueling has to be slower or the gas has to be pre-cooled before refueling, which is energy-intensive. In some cases, for safety reasons, refueling must be automatically interrupted if the maximum temperature is reached or exceeded.

the U.S. 9,476,650 B2 discloses a heat exchanger for underwater use. This comprises a plurality of tube bundles of equal length, each of which comprises a plurality of tubes wound helically about a central axis. Each tube bundle is surrounded by a tube jacket. End pieces are arranged on both sides along the central axis and are connected by an outer wall in the shape of a cylinder jacket. The end pieces have openings in which the pipes and the pipe jackets are accommodated on both sides.

From the CN 105910467A a horizontally arranged heat exchanger is known, with a cylindrical outer shell in which a tube bundle is arranged. The tubes of the tube bundle are connected to end chambers on both sides, which have inlet and outlet connections for a first fluid. For its part, the outer casing has inlet and outlet connections for a second fluid. The inlet ports are each located at the top and the outlet ports are located at the bottom. The tube bundle has a straight center tube running along a center axis and a plurality of helical outer tubes arranged around the center tube.

the CN 203550678 U discloses a cooler having a housing in which are disposed a plurality of tubes communicating with an oil inlet and an oil outlet at opposite ends of the housing. The pipes are surrounded by a cylindrical outer shell that has a water inlet and a water outlet. A plurality of groups of tubes arranged concentrically to one another are provided, with the tubes of a group each having the same distance from a central axis of the housing. Furthermore, it is provided that the tubes are wound in a helical shape, with the winding of mutually adjacent groups of tubes being in opposite directions.

the U.S. 9,964,077 B2 shows a heat exchanger which has a housing which encloses at least two bundles of tubes which are connected on either side to a header each. Each of the bundles comprises a plurality of tubes helically wound about a common axis. The helical structure better accommodates thermal expansion of the individual tubes without causing excessive axial force on the headers.

In view of the prior art shown, the efficient design of the filling process in a compressed gas tank of a motor vehicle still offers room for improvement.

The invention is based on the object of enabling efficient filling of a compressed gas tank of a motor vehicle.

According to the invention, the object is achieved by a method having the features of claim 1, with the dependent claims relating to advantageous refinements of the invention.

It should be pointed out that the features and measures listed individually in the following description can be combined with one another in any technically meaningful way and show further refinements of the invention. The description additionally characterizes and specifies the invention, in particular in connection with the figures.

The invention provides a method for producing a compressed gas tank for a motor vehicle. The motor vehicle can be, for example, a car or truck. The compressed gas tank may also be referred to as a liquid gas tank and is normally used to hold a pressurized gas that is used to power the motor vehicle, e.g. hydrogen for a fuel cell or natural gas (compressed natural gas, CNG), dimethyl ether (DME ) or Autogas (Liquefied Petroleum Gas, LPG, usually a mixture of butane and propane) for a correspondingly equipped internal combustion engine. Due to the high pressure, the gas may be completely or partially in a liquefied state within the compressed gas tank in the operating state. Nevertheless, the term "gas" is used here for the sake of simplicity, since this also corresponds to the state of aggregation under normal conditions in these cases.

According to the method, a housing of the compressed gas tank is provided, which has an axially extending housing opening. Within the housing, of course, an interior space is formed which, in the operating state, serves to accommodate the pressurized gas. In this context, the “axial direction” is defined as the direction in which the housing opening extends and passes through the housing wall of the housing. However, the axial direction can also correspond to a housing axis, along which the housing extends and to which it is at least partially symmetrical. With regard to the further construction of the housing, there are different possibilities. For example, the housing could have a tangentially encircling center section and two end sections connected to it at the axial ends. The end sections can be prefabricated separately from the middle section, so that the housing is composed of at least three parts, which are generally surrounded by an outer casing as a whole, as described below. With regard to the axial direction, the middle section is designed to be tangential, i.e. it surrounds the housing axis in the manner of a cylinder jacket. Normally, the cross section of the central portion is circular and at least approximately constant along the axial direction. At the axially opposite ends of the central section, one end section is connected to the central section, it also being possible for the sections mentioned to be manufactured in one piece with one another. Alternatively, the end sections can be manufactured separately, in which case one can also speak of end pieces. The shape of the respective end section can be convex (or possibly also concave) at least in sections. In the configuration described here, the housing opening is formed in one of the end sections or end pieces and can in particular be formed symmetrically to the housing axis. With regard to the materials of the housing, there are no restrictions within the scope of the invention. Typically, the end pieces are made of metal, such as aluminum. The middle section can, for example, consist of a polymer or also of a metal. The housing parts described here can in particular form an inner jacket or liner of the housing, which is completely or partially wrapped on the outside with bundles (so-called rovings) made of endless fibers, e.g. carbon fibers, glass fibers, aramid fibers etc. or mixtures of different fibers, which in turn are are integrated into a polymer matrix. This fiber reinforcement can in particular improve the pressure resistance of the tank. Typically, one of the following types of pressurized gas tanks is manufactured: all metal tanks, metal tanks reinforced with fiber laminate in the middle section, metal tanks completely reinforced with fiber laminate, or tanks with a polymer middle section and metal end pieces and complete with Fiber laminate are reinforced.

In a further step of the method, a bundle of heat-conducting elements is at least partially inserted with a first end first through the housing opening into the housing. In the fully assembled state, the heat-conducting elements serve to dissipate heat from the interior of the housing. This is particularly advantageous when filling the pressurized gas tank, during which it could heat up considerably, mainly due to the compression of the gas. However, since at least part of the heat generated by compression can be given off to the heat-conducting elements and dissipated via them, the heating of the pressurized gas tank is limited, so that a maximum temperature of the tank specified for safety reasons can be more easily maintained. This in turn has the advantage that refueling can be carried out more quickly without the gas having to be pre-cooled.

In order to optimally fulfill their function, the heat-conducting elements are normally made of metal, e.g. stainless steel. Optionally, you can have a surface coating, which should, however, be selected in such a way that it does not significantly restrict the thermal conductivity. In general, each heat conducting element can be referred to as elongate, so that it has an extension along a direction, which can be referred to as the longitudinal direction or the direction of extension, which normally corresponds to at least five times or at least ten times an extension transverse to the direction of extension. The external cross-section of a thermally conductive element can be designed in different ways, for example polygonal, rectangular, oval or, in particular, circular. Normally, the external cross-section is constant along the entire length of the heatsink, but it could vary. The bundle has a plurality of heat-conducting elements, the number of which can be between 4 and 20 or between 6 and 15, for example. Within the bundle, each heat conducting element is normally located adjacent to at least one other heat conducting element, typically at least two other heat conducting elements. In particular, it can touch at least one other heat-conducting element, at least in some areas. The bundle has a first end and is inserted at least partially into the housing with the first end first (or foremost) through the housing opening. The direction of movement during insertion can correspond at least approximately to the axial direction, for example it can deviate from the axial direction by less than 20°. As will be explained below, the bundle is preferably only partially inserted, e.g. it can be inserted with 50% to 80% of its length, while the remaining 20% to 50% initially remain outside the housing. The insertion of the bundle can be done manually, but preferably it is done automatically.

After at least partial insertion, at least one force is applied to a second end of the bundle, causing the bundle to expand radially within the housing. The second end of the bundle is arranged opposite to the aforesaid first end, i.e. it is arranged behind with respect to the direction of movement of the insertion. Typically, it is still located outside the housing after (partial) insertion of the bundle. At least one force is applied to the second end. The force can be applied directly or via at least one intervening element. Although the at least one force could in principle be applied manually, for reasons of precision it is preferred that it is applied automatically. In particular, it can also be a matter of a couple of forces, which corresponds to a torque. Strictly speaking, the at least one force is applied to the second end relative to the first end. This means that at the same time a counterforce acts on the first end, which prevents the bundle from simply moving in its entirety as a result of the action of the force mentioned. Application of the at least one force causes the bundle to radially expand within the housing. That is, if one considers the expansion of the entire bundle transversely to the axial direction, namely in the radial direction, this expansion increases when the at least one force is exerted. One could also say that the individual heat-conducting elements of the bundle move away from one another, so that the bundle as a whole expands or spreads out. The expansion or spreading does not normally take place along the entire length of the bundle, but only in certain areas. In particular, it does not have to be uniform in all areas of the bundle.

In any case, the expansion of the bundle improves the effectiveness of the cooling that can be achieved by the heat-conducting elements. In this case, the heat-conducting elements of the bundle can first be introduced in a relatively compact form through the housing opening and then spread open in the manner described, as a result of which they can cool a larger volume area of the interior. In this case, it can be assumed for the sake of simplicity that each heat-conducting element contributes to the cooling of a certain area in the vicinity of the heat-conducting element. In the compact form in which the bundle is inserted, the corresponding areas of the heat conduction elements can overlap, which can affect cooling. In addition, there may initially be no or only minimal gaps between the heat-conducting elements, so that gas to be cooled cannot get between the heat-conducting elements, or only with difficulty. After expansion and spreading, there are normally sufficient gaps so that each heat-conducting element contributes to the heat exchange with its entire surface.

The course of the individual heat-conducting elements within the bundle can vary. For example, the heat-conducting elements could be arranged straight when inserted. According to a preferred embodiment, a bundle of helically wound heat-conducting elements is introduced. That is to say, at least during insertion, the heat-conducting elements are wound helically within the bundle, i.e. in the manner of a helical line or in the manner of a helical line. Considered individually, each heat-conducting element runs helically. Overall, it can be said that the heat-conducting elements are wound around one another or are wound at least approximately around a common bundle axis. All heat-conducting elements of the bundle are wound in the same direction or in the same direction.

In principle, it would be conceivable for an axial force to be exerted on the second end, as a result of which the bundle is compressed in the axial direction and at the same time expands in the radial direction. This would be possible regardless of the course of the heat-conducting elements, ie they could be straight, helically wound or shaped in some other way. In this case, however, the deformation of each heat conducting member may be difficult to control. In addition, an axial force of considerable size may be necessary, which in turn must be compensated for by a corresponding counter-force on the first end. If the first end transmits the force to the housing, for example, there could be a risk of damage to the housing. According to a preferred embodiment, a torsional moment is exerted on the bundle by the at least one force, as a result of which the winding of the bundle is reduced. It can also be said that the torsional moment opposes the twisting of the bundle. Of course, at least one force couple is necessary for a torsional moment. The torsional moment causes the second end to rotate relative to the first end. The reduction in winding is usually accompanied by a shortening of the bundle, ie the distance between the first and second ends decreases. In particular, the second end may initially be located outside the housing, while after the end of the spreading it is located inside the housing, e.g. within the housing opening.

As already explained, the at least one force or torque acting on the second end must be compensated by an opposing force or torque on the first end in order to prevent twisting or displacement of the entire bundle. The housing usually has a second housing opening opposite the above-mentioned housing opening. In principle, it would be possible to grip the first end from the outside through this second housing opening and thus stabilize it while the force is being exerted on the second end. However, this procedure is generally complicated. It is thus preferred that the first end of the bundle is connected in a torque-transmitting manner to an engagement region of the housing axially opposite the housing opening, after which the torsional moment is exerted. The connection is at least torque-transmitting and can in particular be non-rotatable, so that the first end cannot rotate relative to the housing. The torque can be transmitted, for example, by means of a force fit, possibly by means of a material connection and/or in particular a form fit.

The bundle is preferably connected at the first end in a torsion-proof manner to an engagement element, which is brought into engagement with the engagement area in a form-fitting manner. The first engagement element can be connected to the heat-conducting elements of the bundle in a form-fitting, force-fitting and/or material-fitting manner. For example, it can have continuous recesses or recesses which are open towards the second end and in which the heat-conducting elements are accommodated at the ends. On an opposite side, which faces the engagement area, the engagement element has structures that enable a form fit, in particular a form fit in the tangential direction. This can be, for example, axial projections and/or recesses. These correspond to structures of an intervention area. For example, the first engagement element could have a projection that can be inserted into a recess of the engagement area, or vice versa. The positive fit prevents the first end from twisting relative to the engagement area. It would also be conceivable for the engagement element to have an external thread which is screwed into an internal thread which is formed in the engagement area.

As already explained above, the bundle can be inserted through the housing opening in a compact form and then expand radially, as a result of which a more effective, more uniform cooling of the interior of the housing is possible. In particular, during expansion, a radial expansion of the bundle can increase at least in regions by at least 100%, possibly also by at least 200%. For example, the bundle could easily be passed through an end opening with an outside diameter of less than 5 cm and then be spread to an outside diameter of 10 cm, 15 cm or more.

The expansion is preferably based on an at least predominantly elastic deformation of the heat-conducting elements. The same applies to reducing the winding of the bundle. There is therefore no or at most negligible plastic deformation of the heat-conducting elements. Such plastic deformation, which would be associated, for example, with at least locally exceeding the yield point, could have a disadvantageous effect on the durability of the heat-conducting elements. This combined with larger temperature differences could lead to cracks in the heat conducting elements. In addition, in the case of plastic deformation, there is a risk that the cross sections of the through-channels will decrease and the flow will be impeded. Whether the range of elastic deformation is maintained can be checked on the basis of the specific deformation and the known material properties of the heat-conducting elements.

The heat-conducting elements can be solid, for example as metal rods, which dissipate heat from the interior of the compressed gas tank solely due to heat conduction. According to a preferred development, however, at least one heat-conducting element has a through-channel for a coolant. In particular, this can relate to all heat-conducting elements. The respective heat-conducting element has a passage input channel, which is continuously formed along the entire length of the heat-conducting element. The heat-conducting element can thus be referred to as hollow or at least tubular in the broadest sense. In this case one can also speak of a heat pipe. The cross-section of the through-channel can be designed in different ways, for example polygonal, rectangular, oval or, in particular, circular. Normally the cross-section is constant along the entire length of the heat-conducting element, but it could also vary. It would be conceivable for a heat-conducting element to have a plurality of through-channels, but normally each heat-conducting element has exactly one through-channel.

In this case, it is provided that the respective through-channel is or will be connected at least indirectly to two coolant connections, which in particular can each be arranged on one of the end sections. The connection is usually made before the bundle is inserted into the housing. The two coolant connections form an inlet and an outlet for coolant. In this case, of course, one end of the through-channel is connected (directly or indirectly) to one coolant connection, while the other end is connected to the other coolant connection. The coolant connections can be connected to a coolant circuit of the motor vehicle when the compressed gas tank is installed. In other words, when installed, the compressed gas tank is integrated into the coolant circuit, with the coolant flowing in through one of the coolant connections (which can also be referred to as the inlet coolant connection) and flowing out again through the other (which can also be referred to as the outlet coolant connection). . In this case, the coolant is also guided through the through-channel due to the described connection of the through-channel to the coolant connections. In particular, it can be provided that the through-channels have a group of first through-channels and a group of second through-channels, the first through-channels being arranged upstream of the second through-channels. Thus, the first through-channels are connected to the outlet coolant port via the second through-channels (and possibly further lines or channels), while the second through-channels are connected to the inlet coolant port via the first through-channels (and possibly further lines or channels). As an alternative to a coolant circuit of the motor vehicle, an at least partially external coolant circuit could also be used, e.g. a coolant circuit of a filling station for the compressed gas tank.

Since the through-channel is formed inside the heat-conducting element, which in turn runs through the interior of the compressed gas tank, heat can be exchanged between the coolant in the through-channel and the gas in the interior of the compressed-gas tank. In this case, the heat is transported not only by heat conduction, but above all by convection, i.e. by the flow of coolant in the through-channel. In general, this is much more effective than transporting heat solely by conduction. The coolant can be a conventional liquid coolant for motor vehicles, for example a water-glycol mixture. This can also be used to cool or temper other components of the vehicle. The heat that is transferred from the compressed gas to the coolant can be given off to the surroundings of the vehicle at another point via a radiator or, alternatively, can also be used to heat the vehicle interior.

According to one embodiment, the heat conducting elements are connected to one another at the second end by a head element and an external thread of this head element is screwed into an internal thread of the housing opening. That is, the housing opening has an internal thread which cooperates with an external thread which is formed on the head element. The head element, like the heat-conducting elements, can be made of metal and can have, for example, recesses in which the ends of the heat-conducting elements are accommodated in a form-fitting manner. Screwing the head member into the housing opening secures the second end to the housing. In this case, of course, the second end is also rotated, by means of which the coiling of the bundle is reduced and the bundle can be spread open at the same time. In the embodiment described here, both coolant connections can be arranged on the head element, while at least one deflection channel is formed on the engagement element. Each deflection channel connects at least one first through-channel to at least one second through-channel and can be U-shaped. A first collection channel, which is connected to the inlet coolant connection, and a second collection channel, which is connected to the outlet coolant connection, can be formed in the head element. The first collecting duct can be connected to the first passage ducts via first branch ducts, while the second collecting duct is connected to the second passage ducts via second branch ducts. Each of the collecting channels can be ring-shaped.

The head element can in turn have an axial through-opening into which a valve or a closure element is introduced and therein is secured. In this case, the through-opening can be centered in particular with respect to the housing axis and the ends of the heat-conducting elements can be arranged (radially spaced) around the through-opening. Likewise, the through-opening is normally arranged concentrically to the above-mentioned housing opening. A valve can be introduced into the passage opening and, for example, screwed in, which can then be used to fill the compressed gas tank. In other words, in this case the compressed gas tank is filled from the side of the (first) housing opening. Alternatively, it can be provided that the compressed gas tank is filled from the opposite side, in which case a corresponding valve is arranged there. The (first) housing opening can then be closed by a closure element (end plug), which can also be secured, for example, by screwing.

• 1-4 eine Schnittdarstellung eines Druckgastanks während verschiedener Phasen eines erfindungsgemäßen Verfahrens;
• 5-7 eine Detailansicht eines Bündels von Wärmeleitrohren während verschiedener Phasen des erfindungsgemäßen Verfahrens;
• 8 eine perspektivische Darstellung des Bündels mit einem Kopfelement;
• 9 eine teilweise Schnittdarstellung eines Teils des Bündels mit dem Kopfelement aus 8;
• 10 eine Schnittdarstellung entsprechend der Linie X-X in 9; sowie
• 11 eine teilweise Schnittdarstellung eines Teils des Bündels mit einem Eingriffselement.

Further advantageous details and effects of the invention are explained in more detail below with reference to exemplary embodiments illustrated in the figures. Show it

• 1-4 a sectional view of a compressed gas tank during different phases of a method according to the invention;
• 5-7 a detailed view of a bundle of heat pipes during different phases of the method according to the invention;
• 8th a perspective view of the bundle with a head element;
• 9 Figure 12 shows a partial section view of part of the bundle with the header 8th ;
• 10 a sectional view taken along the line XX in 9 ; such as
• 11 a partial sectional view of part of the bundle with an engaging element.

In the different figures, the same parts are always provided with the same reference numbers, which is why they are usually only described once.

1 shows a sectional view of a compressed gas tank 1 for a motor vehicle, which can be used in a car, for example, during a first phase of a method according to the invention. The cutting plane in 1 runs parallel to a housing axis A, which corresponds to an axial direction. The housing axis A forms an axis of symmetry of the compressed gas tank 1. This has a housing 2 with a central section 3 in the shape of a cylinder jacket, which is adjoined at the axial end by a first end section 4 and a second end section. The representation of the housing 2 is greatly simplified here. Typically, this has an inner sheath of plastic and/or metal surrounded by an outer sheath consisting of rovings (continuous fibers) wound in a polymer matrix. An axially extending housing opening 4.1 is formed on the first end region 4 in the region of the housing axis A. An engagement area 5.1 is formed in the second end area 5, the function of which will be explained below.

Furthermore, in 1 a bundle 10 of coolant tubes 11 can be seen, which are helically wound around one another. In the present example, the coolant tubes 11 are made of stainless steel. Each coolant tube 11 has a through-channel 11.1, 11.2, with a group of first through-channels 11.1 and a group of second through-channels 11.2 being functionally distinguishable, which will be explained below. At a first end 10.1, the coolant pipes 11 are connected to one another by an engagement element 12, which has an engagement structure 12.1 designed in the manner of a projection. This is designed to complement an engagement structure 5.1 of a second engagement element 5.2 formed in the end region 5. The ends of each coolant tube 11 can be accommodated and, for example, screwed into recesses (not shown here) in the respective engagement element 12 . The coolant tubes 11 could therefore first be screwed into the engagement element 12 and then twisted before being inserted into the compressed gas tank 1, so that the illustrated helical configuration can be achieved. However, it is also conceivable that the coolant pipes 11 winding around each other in a helix-like manner are held in a rotationally fixed manner by the engagement element 12 , a force-fitting, material-fitting or form-fitting connection being considered. For example, the engagement element 12 can be sleeve-like and hold the bundle on the outside in a non-rotatable manner, with the engagement structure 12.1 being arranged on a closed end of the engagement element 12. As in 11 As can be seen, the engagement element 12 has a plurality of U-shaped deflection channels 12.2, each of which connects a first through-channel 11.1 to a second through-channel 11.2. At a second end 10.2, the coolant tubes 11 are connected by a head element 13, which is shown in the enlarged representations of FIG 8-10 is better recognizable. The head element 13 is ring-shaped overall and has an external thread 13.1 and an internal thread 13.3 in a through-opening 13.2. Furthermore, a plurality of first branch ducts 13.4 are formed, which are each connected to a first through-duct 11.1 of one of the coolant pipes 11, and a plurality of second branch ducts 13.5, which are each connected to a second through-duct 11.2 in connection. The first branch ducts 13.4 are connected to an inlet coolant connection 13.8 via an annular first collecting duct 13.6, while the second branch ducts 13.5 are connected to an outlet coolant connection 13.9 via a second collecting duct 13.7, which is also annular. Both coolant connections 13.8, 13.9 are arranged on the head element 13.

In 1 the bundle 10 is partially inserted with the first end 10.1 first through a continuous housing opening 4.1 in the axial direction on the first end region 4 into an interior space 2.1 of the housing 2. The direction of movement during insertion corresponds at least approximately to the axial direction.

In 2 When the bundle 10 is inserted so far that the first engagement element 5.2 positively engages with the second engagement element 12, which prevents the engagement element 12 from twisting relative to the housing 2. The length of the bundle 10 is dimensioned in such a way that part of it with the head piece 13 is still outside of the housing 2 . In the further course, a torque (corresponding to a force couple) is exerted on the second end 10.2, which leads to a torsional moment acting on the bundle 10. This state is also in 5 shown with only part of the bundle 10 visible.

As it progresses, the applied torque causes the bundle 10 to decrease in turn while at the same time reducing its length in the axial direction. Thus, the radial dimension of the bundle 10 (its outer radius) increases within the compressed gas tank 1, while the head piece 13 is moved closer to the housing opening 4.1. this is in 3 as in 6 shown.

The process described continues until, as in 4 and 7 shown, the bundle 10 is spread out to such an extent that its radial dimension has increased by more than 200% compared to the original state. It thus fills the interior 2.1 of the housing 2 much better than in the original state according to FIG 2 . In addition, clear gaps between the individual heat pipes 11 can be seen. The entire spreading of the bundle 10 takes place through elastic deformation of the individual heat-conducting tubes 11. Finally, the external thread 13.1 of the head piece 13 is screwed into an internal thread 4.2 of the housing opening 4.1. The direction of rotation for screwing in is selected in such a way that the bundle spreads further. In addition, a valve 14, shown here in a highly schematic manner, can be screwed into the through-opening 13.3. The interior 2.1 of the housing 2 can be filled with a pressurized gas (e.g. hydrogen, natural gas, DME or LPG) via the valve 14, which is used to drive the motor vehicle.

When installed, the passage channels 11.1, 11.2 of the coolant pipes 11 can be connected to a coolant circuit of the motor vehicle, which carries a liquid coolant (e.g. a water-glycol mixture) and for temperature control, i.e. cooling and/or heating, of various vehicle components or - areas. More precisely, the inlet coolant connection 13.8 is connected to a supply coolant line (not shown), while the outlet coolant connection 13.9 is connected to a discharge coolant line. In this way, coolant can reach the first through-channels 11.1 via the inlet coolant connection 13.8, the first collecting channel 13.6 and the first branch channels 13.4. From there, the coolant reaches the second through-channels 11.2 via the deflection channels 12.2, and further via the second branch channels 13.5 and the second collecting channel 13.7 to the outlet coolant connection 13.9. From there it gets into the discharging coolant line. When the motor vehicle is being refueled, liquid gas is filled into the compressed gas tank 1 from an external tank via a tank line and the valve 14 . When it flows into the pressurized gas tank 1, the gas flows through the spaces between the coolant tubes 11 and has relatively large-area contact with the coolant tubes 11. This results in heat exchange between the gas, which heats up during filling, and the coolant in the passage channels 11.1 11.2. The heating of the gas is limited by the heat exchange with the cooling liquid that takes place via the wall of the respective coolant pipe 11 . This can prevent the temperature of the gas or the pressurized gas tank 1 from exceeding a threshold value specified for safety reasons, even when filling up relatively quickly. An external pre-cooling of the gas is not necessary for this. The heat absorbed by the coolant is dissipated via the coolant circuit and can, for example, be given off to a vehicle interior or also to the vehicle environment via a heat exchanger. As an alternative to a cooling circuit of the motor vehicle, a connection to a (partially) external cooling circuit would also be conceivable, which is assigned to the filling station at which the compressed gas tank 1 is filled up.

Reference List

1

compressed gas tank

2

casing

2.1

inner space

3

middle section

4, 5

end section

4.1

case opening

4.2, 13.3

inner thread

5.1

intervention area

5.2, 12.1

engagement structure

10

bunch

10.1

first end

10.2

second end

11

heat pipe

11.1, 11.2

through channel

12

engagement element

12.2

deflection channel

13

headpiece

13.1

external thread

13.2

passage opening

13.4, 13.5

branch channel

13.6, 13.7

collection channel

13.8

Inlet coolant connection

13.9

Outlet coolant connection

A

housing axis

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• US9476650B2 [0003]
• CN 105910467A [0004]
• CN 203550678 U [0005]
• US 9964077 B2 [0006]

Claims (9)

Method for producing a compressed gas tank (1) for a motor vehicle, wherein a housing (2) of the compressed gas tank (1) is provided that has an axially extending housing opening (4.1), a bundle (10) of heat conducting elements (11) with a first End (10.1) first is at least partially inserted into the housing (2) through the housing opening (4.1) and thereafter at least one force is exerted on a second end (10.2) of the bundle (10), whereby the bundle (10) is inside the housing (2) radially expanded. procedure after claim 1 , characterized in that a bundle (10) of helically wound heat-conducting elements (11) is introduced. procedure after claim 2 , characterized in that a torsional moment is exerted on the bundle (10) by the at least one force, whereby the winding of the bundle (10) is reduced. procedure after claim 3 , characterized in that the first end (10.1) of the bundle (10) is connected in a torque-transmitting manner to an engagement region (5.1) of the housing (2) axially opposite the housing opening (4.1), after which the torsional moment is exerted. procedure after claim 4 , characterized in that the bundle (10) at the first end (10.1) is non-rotatably connected to an engagement element (12) which is positively brought into engagement with the engagement area (5.1). Method according to one of the preceding claims, characterized in that the expansion is based on an at least predominantly elastic deformation of the heat-conducting elements (11). Method according to one of the preceding claims, characterized in that at least one heat-conducting element (11) has a through-channel (11.1, 11.2) for a coolant. Method according to one of the preceding claims, characterized in that the heat conducting elements (11) are connected to one another at the second end (10.2) by a head element (13), and an external thread (13.1) of this head element (13) into an internal thread (4.2) of the housing opening (4.1) is screwed in. Method according to one of the preceding claims, characterized in that the head element (13) has an axial passage opening (13.2) into which a valve (14) or a closure element is introduced and secured therein.

Images